


Stiles' is finally an Official Omega

by SterekFangirl



Series: Young Sterek Love [7]
Category: Teen Wolf (TV)
Genre: Alpha Derek Hale, Anal Fingering, Anal Sex, M/M, Mates Derek Hale/Stiles Stilinski, Mating Cycles/In Heat, Omega Stiles Stilinski, Smut, mention of MPREG
Language: English
Status: Completed
Published: 2018-12-26
Updated: 2018-12-26
Packaged: 2019-09-28 05:15:27
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 5,617
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17176598
Author URL: https://archiveofourown.org/users/SterekFangirl/pseuds/SterekFangirl
Summary: Stiles is finally an official Omega and Derek is there to experience it with him.





	Stiles' is finally an Official Omega

**Author's Note:**

> Hey! Sorry, this is so late but my laptop died after only a few years but I got a new one for Christmas so here you go. This is SMUT!!! Keep in mind that this is my first time writing smut. Viewer discretion is advised. If you are underaged or immature turn back now and just skip this fic. The rest of the series will make sense without, just know that Stiles goes into heat and becomes an official Omega.

Stiles had been acting weird the night before, but Derek had dismissed it, thinking that ‘hey, the kid’s always weird’. Stiles was oddly quiet and kinda shy, even at his own home, but Derek hadn’t thought much about it.  
He’d just wrapped his mate up in a blanket, pulled out one of the hoodies Stiles kept for himself and kissed the boy’s head in goodnight. The Omega grumbled happily, but Derek missed it when a pale, moled hand reached out for him as he turned his back and left. 

Derek drove him and Stiles to school in his Camaro and smiled as his mate scarfed down the food Derek had provided. Well, brought him because his mom bought it, but still. He felt a warm feeling in the well of his chest, where his wolf stayed, typically under control.  
He dropped Stiles off at the middle school and parked between the schools that shared a campus. His mate stumbled out of the car, his legs a little wobbly and his head hung as he walked into the school, swaying back and forth a little which concerned Derek a little bit.  
Stiles seemed fine other than that though and waved happily at Derek. That’s what really assured him. Stiles was happy, his smell sweet and his eyes wide and gleeful.  
It had actually calmed Derek down a little, and Stiles was off, bounding off with Scott and Allison. There was nothing about him that seemed wrong. In fact, Derek felt like everything was specifically right at the moment.  
Derek himself sauntered into school, his chin held high, and he felt good. His chest felt full, in a nice way. He wasn’t quiet smiling, but his face was definitely less...grr than usual. He wasn’t sure why he felt so good right now, but he did and was savouring it.  
There was nothing to stop him that day, he was on point. He got a good grade on a test he thought he’d failed, this creepy girl Kate had left him alone today, and yeah. Not too shabby of a day. Oh god, he’s turning into Stiles minute by minute. 

The hallways were full of people, clogged with teenagers so loud it rivalled a football stadium. There was a pep in his step, and he heard the annoying ring of a phone, and almost yelled for someone to turn that stupid thing off.  
He walked into the cafeteria to find Boyd and Erica already sitting at a table. He didn’t bother with lunch because he and Stiles were supposed to go to the diner after school. There was nothing on his mind except for his little Omega, and how he hoped the boy was having a good day. As he sat down he decided to text the boy and pulled out his phone.  
Turning it on he realized he missed four calls. Apparently, the annoying person who wouldn’t answer their phone in the hallway was him. He checked the caller, mildly annoyed, before realizing the caller had been the middle school.  
He was the emergency contact for Stiles as he was the Omega’s mate, and now the school was calling him. He swallowed and tried desperately to hear the messages on his phone but couldn’t hear it.  
Derek ran out of the cafeteria, into the vacant halls, and plugged his other ear so he could hear the message. “Hello, Derek. There is a situation with Mie-Mik-” The caller gave up trying to say the boy’s real name, “Stiles Stilinski, and we have asked the high school and you’ve been granted permission to join us here in the nurse’s office at the middle school.” It was the same message over and over again. Derek hung up and didn’t even think to tell Erica and Boyd about the call, instead sprinting over to the middle school immediately, using his werewolf speed, and following the smell of his mate. It was sweet and overpowering and overwhelming, wrapping Derek up in the warm comfort of OMEGA.  
He burst into the nurse’s office, a place he’d only ever been in once before, and found his mate, sitting on his knees and snarling occasionally. He’d heard Stiles growl once or twice before and...fuck that was attractive. Derek pushed that thought away and focused all his senses on his little boy perched on the edge of the nurse bed.  
Stiles must have smelled his Alpha because his head shot up and his eyes widened before whining happily. As Derek approached him he noticed that the sheriff was there too, and that’s what his Omega had been growling at. The sheriff looked stunned and was standing there, his arms limp at his side.  
Derek approached the bed and smiled warmly at his mate, a smile everyone knew he saved specifically for Stiles. He got close enough and crouched by the bed, picking up the slip of a kid that was his mate. Stiles’ legs locked around Derek’s waist, arms around the Alpha’s neck, and had his head buried in Derek’s neck. There was nothing more pleasant than the feeling of his Omega’s warm breath on his neck. Stiles clung to Derek like a tiny monkey, making happy noises and grateful whimpers.  
“What’s going on?” He demands of both the nurse and the sheriff. He crossed his arms underneath Stiles’ ass, supporting him as he rocked them both, gently, soothing Stiles’ sad little noises.  
The nurse answered first and watched Derek and Stiles carefully as the boy settled in the Alpha’s arms and fell into that sweet, nuzzly, affectionate mode where he was basically a baby koala. Derek cooed quietly to Stiles as the nurse explained the situation. “Stiles had been acting strangely in all his classes, and he couldn't focus. He was in his science class when he...well I don’t really know. He started growling at all the Alphas, and one of the students reported that he...he uh smelled pleasant. The only person he would allow near him was a fellow Omega, Lydia. He didn’t speak but he seems much more...much calmer now. When his father was contacted he wouldn’t even let the sheriff touch him. He was shaking and crying earlier and was making loud, desperate noises. He’s calmed down significantly since then, and it appears he has sunken into pre-heat OmegaSpace.”  
“Pre-heat?” John squeaked and Derek glared. Derek had known that his Omega was approaching his first heat, being as he had his first shift, and his body had begun maturing.  
“Yes Sheriff, his body is desperate for his Alpha, trying to prepare the both of them for his first heat.” The nurse continued to stare at Derek and his mate as Stiles calmed as Derek cradled his ass. “I would recommend that Derek take his mate to his home, or somewhere they will both feel safe. Stiles may soon go into heat soon and it would be a bad idea for an Alpha-,” Derek growled angrily at even the briefest mention of some obscure Alpha, “Or an unmated Omega-” This time Stiles growled, angry that other Omegas even existed, and territorial about his mate. “To be around either of them, especially Stiles, as he is being wracked with hormones and could react one of two ways; in blatant and violent anger, or crushing self-consciousness and could collapse into himself,” The nurse finished and Derek nodded. He readjusted Stiles higher up on his chest and removed a hand from the boy’s ass, laying it on the back of his Omega’s neck and gently pushing Stiles’ head further into the crook of his neck.  
Derek knew this next part was going to be rough on the younger boy. As much as Alphas were possessive and territorial, Omegas were built to protect their nest and cubs, and could, therefore, be very scary. He couldn’t even imagine his little boy being scary, instead finding it attractive. Still, he didn’t want his mate to hurt another student, and he especially didn’t want Stiles to hurt himself.  
Derek held the boy closer to himself. “Baby, get my keys from the left pocket of my jacket.” It was a simple command, one with the sole purpose of easing Stiles into OmegaSpace comfortably. Well...and he needed his keys to start the Camaro. He felt a soft little hand digging around in his jacket pocket before hearing the familiar jangle of keys.  
Apparently, Stiles became entranced with the keys, playing with them behind Derek’s back. Stiles, in OmegaSpace, reminded Derek of Cora when she was little and would get sick. She, like Stiles, was incredibly needy and acted more like a child than ever.  
The Omega was quiet besides the tiny sounds of amusement he made as he played with the keys. That is until some tiny sixth-grade Omega walked down the hall and Stiles snarled viciously before calming down as Derek hushed him and rubbed over his back, soothing his desperate mate.  
Stiles growled a bit more before slumping against Derek, almost like he’d fallen asleep. Derek knew that he hadn’t, because Stiles tiny hands (or tiny compared to his) were clutching everywhere they could get to. He whined and Derek nearly had a heart attack when Stiles rubbed his front, his tiny little Omega cock, against the solid abs Derek had gained through boxing and lacrosse. Derek grunted before he picked up the pace, making it to the car as quick as possible.  
They made it out of the school and into the car in record-breaking time. He tried to place Stiles in the passenger seat, where he usually sat, but his mate whined, high and heartbroken, desperate and needing as much love and physical contact as possible.  
Derek sighed and scooted the car seat as far back as he could, making room for the both of them. Luckily Stiles was tiny because he was an Omega and Derek wasn’t exactly a bodybuilder so they were able to fit behind the wheel, Stiles curled into his lap and suckling on the collar of Derek’s shirt. It was adorable and reminded Derek of a pup, which made his coo even more. Stiles made happy little sounds as Derek rubbed him up and down, sliding a big hand over the smaller boy’s ass.  
There was nothing more satisfying than hearing the content little purr Stiles let out, of that Derek was sure. 

They pulled into the Hale House drive and Derek killed the car and clutching at the Omega’s hips before unloading them both from the car. Stiles shifted around as Derek carried him, and Derek tried to keep his breathing even. The boy was 14, while Derek’s birthday was two days away when he’d turn seventeen, so they weren’t necessarily illegal because they were both still minors, but he still felt mildly shady.  
Everybody in town knew, not necessarily understand or support them, but they all knew. They’d all seen them together, constantly ever since the two very first met, and not many people had outright mentioned or shown their disgust or disapproval, except for a few explosive occasions.  
Now, he didn’t feel that familiar wariness. He was never nervous or ashamed of being mated to Stiles, no matter the age difference, but Derek knew his mate was picked on because of it, and he never wanted to do anything that made Stiles uncomfortable or inadvertently made the boy a target. 

Derek carried Stiles into the house, cuddling the boy close and thanked all the gods he knew of that everyone was out of the house. He assumed and hopped the sheriff had called his parents and caught them up to speed because he wasn’t sure he’d been able to any time soon. 

Stiles refused to let go of his Alpha and clung on as Derek sat down on the bed. That certainly didn’t make his situation any better, as Stiles sat in his lap, all his weight rested on Derek and his little ass was pushed down on his crotch as Stiles wiggled about, trying to get comfortable in his mate’s lap.  
There were very few layers between Derek’s body and Stiles. Derek tried not to pay attention to that fact as he cooed at Stiles, rubbing the Omega’s back gently and trying to soothe the whimpers that flowed from the boy’s mouth. “Shhh little one,” He muttered at his tiny mate. Here, looking like this, it was so obvious that Stiles was an Omega. The little fox was just that, tiny, and his proportions were spot on. His legs were long, despite his height, his hips filled out his frame, and his shoulders were broader than most girls, but he was still slimmer than most other men.  
Everyone always told them that Stiles would shoot up in high school and that Derek should be prepared for it, but he doubted that. He doubted that Stiles would ever be as tall, was thick-skinned as himself. Stiles wasn’t a delicate flower by any means, but he was not meant to be beefy, he was meant for pups. Shit, Derek can’t think about things like that. They’re both too young. Stiles himself was still a pup, and Derek was wrong in thinking things like that. Just because he was an Omega didn’t mean he was less of a person or that he was just a machine for Derek to breed, despite most Alpha’s views.  
He kept himself in check and smiled warmly at his Omega to try and calm the sweet boy down. Derek’s mate whined and shoved himself closer and nuzzled at his neck, and Derek pulled Stiles closer by his hips and settling him as he lay them down. 

They fell asleep for a moment, Stiles tired and needy. The room was warm and there was an abundance of blankets on Derek’s bed. When Derek woke he found that there was a wall of blankets around himself and his mate, clearly his little Omega’s doing. Stiles lay in the centre of his chest and snuggled himself close. Derek smiled down at his little boy and lifted his arms to wrap them around Stiles, fanning his hands out over the Omega’s back, pressing Stiles tighter to himself.  


Stiles woke slowly and curled up tighter, bringing himself into a tighter little ball and nosing at Derek’s neck. “Der,” Stiles whined into his neck and then shrunk into himself. “I’m sorry,” He offered.  
Derek could smell the guilt rolling off his Omega and he growled. “No. Don’t be sorry Stiles, it’s natural, I’d be more concerned if you weren’t a little needy. It’s okay baby, I like it, let me take care of it. Take care of you.” Derek sat up, pulling Stiles up with him, still pushed against his chest. The Omega sniffed again, sad and not knowing how to deal with all of these emotions attacking him at once. Stiles eventually settled, after practically burying himself in the scent of his Alpha. He let out tiny little whines, less in pain and more in confusion and disorientation. Derek knew that the pain was fast approaching and he wasn’t sure Stiles would be able to handle it.  
Stiles was still in his possessive, territorial phase when Talia and James returned home. Derek could hear them coming up the stairs and was about to warn them not to enter when Talia opened the door. Stiles lurched off him and out of his lap, instead crouching in front of him and snarling.  
It was kind of funny seeing Stiles so primal and primitive and Derek sitting there. Today the roles were reversed.  
Talia and James looked shocked for a moment before a look of understanding crossing their faces and backing out, closing the door again and retreating down the stairs so as to lessen the perceived threat Stiles’ Omega was facing.  
As Talia and James left Stiles calmed and climbed back into Derek’s lap, his head immediately tucking into the bigger boy’s collarbone and nibbling softly there. Oh no, Derek thought. He knew what that meant. Stiles was getting needy and seeking physical contact. That meant that his heat was about to start. They’d only been suffering through Pre-heat and now the real show was about to begin.  
Derek kept Stiles close to his chest and smiled when the little boy in his arms snuffled cutely, before starting to claw at Derek to get closer. And so it began. 

Derek let the Omega bring himself closer, and he could smell the desperation and pain. The heat had just truly begun and that meant the vicious pain joining the party. Isaac, one of Stiles’ friends had already had his heat and had told Stiles about some of it, who then shared it with his mate.  
Derek knew that Omegas had a high pain tolerance, what with the fact that they had the ‘privilage’ of pushing a pup out, but Stiles had always been a more sensitive Omega and had a lower threshold for pain than Issac.  
Stiles whined again, though this time less childlike and looking for affection, and more in desperate need of pain relief. Derek took in a deep breath, stilled his rioting wolf, and moved his hand down from where it sat between his mate’s shoulder blades.  
He dragged his hand down slowly, letting his Omega seep in as much touch and physical connection as he could, before coming to the recently developed slope of Stiles’ ass. It was firm and Derek hummed as he was finally able to touch it.  
All thoughts of his parents-or even Stiles’ parents-left his mind as his Alpha soothed the Omega. He felt his red eyes flare as he moved his hand down further and slower than before. He listened carefully until Stiles made a soft, squeaky moan. Derek placed his palm firmly there, over his boy’s clothed hole, and began pressing. Stiles nearly screamed, desperate for any gratification he could get. The Omega shoved himself back against the hand on his ass and wiggled in Derek’s lap.  
The Alpha could feel the pressure over his hard dick and nearly purred at the weight of Stiles’ on him.  
Derek shifted, just slightly, but it jostled Stiles’ little cock and made him let out the loudest moan yet. It was powerful and drew Derek’s wolf in. He nosed into the crook of Stiles’ neck and was greeted with the sweetest smell. It was Omega heat and flowers and Stiles and Derek fell under his wolf’s power at that moment.  
He sunk into AlphaSpace, enticed by the scent of a fertile mate, and lifted the Omega off his lap. Stiles whimpered at the loss of contact before realizing what was going on, but powerless in his limp and weak state to help.  
Derek rucked up Stiles’ teeshirt after shedding his own and smiled as he revealed inch after inch of pale, youthful flesh.  
The Omega giggled as Derek’s hand brushed along his ribs and hitched breath as a mouth breathed over his red and flushed nipples. Derek brought his hands down to the skinny jeans his boy was wearing and his wold hummed proudly when he realized they were the ones Derek had bought for his mate. He shoved them down the boy’s thighs, bringing his boxers with them, ignoring the fact that the print was little yellow ducklings. Derek watched happily as Stiles’ was flooded with dopamine and firince, the mating hormone that belonged only to weres until the boy screamed out. The Omega writhed in pain before wriggling out of Derek’s lap and flopping onto the bed to curl into a ball, his back facing Derek.  
Derek took in a laboured breath as he was faced with the light little pink furl for the first time. He’d never seen anything so beautiful.  
Stiles let out another whine and suddenly there was a clear, viscous fluid leaking out and Derek was slammed with the first whiff of his Omega's slick. It was thick and ran slowly down the globe of Stiles’ asscheek. Derek, unable to stop himself, reached out and ran a finger through the rivulet and brought it to his lips, tasting calmly.  
“Oh sweetie,” Derek purred at Stiles, “You taste so good. Let’s make you feel good, eh?” He asked, not bothering to wait for an answer. He shuffled closer and watched as Stiles relaxed a bit more as his Alpha moved closer.  
Derek rested a hand on Stiles' hips and palmed the flesh that pressed against his hand. He ran his second hand down Stiles’ back before running his index finger down the crack of Stiles’ ass until he reached his destination. The Omega whined out loudly and pushed himself against his mate’s hand and wriggled so that the big finger was directly where he wanted it.  
“Calm down baby, I’d hate if I hurt you,” Derek ordered, gently, so as to let his little mate sink further into OmegaSpace. If Stiles’ wasn’t in OmegaSpace when they mated, it wouldn’t calm down the heat and he’d instead just become agitated.  
“Ya won’,” Stiles whined.  
Derek pulled Stiles up again, but this time didn’t pull him into his lap, instead making the boy sat on the bed, on his knees, with Derek’s hand tucked up underneath his ass, making sure there was steady pressure there, slick continuously flowing out and beginning to coat Derek’s entire hand.  
“Okay honey, I need you to let me take care of you. I need you to trust that I’ll make you feel better. I’ll make you feel better.” The boy nodded and with wide eyes leaned closer, all the while trying to push himself down on Derek’s hand to get more pressure where he needed it. “Okay, good baby, such a good boy for me,” Derek cooed, watching as his mate fell further into OmegaSpace. Stiles calmed visibly and Derek took advantage of that. “Baby, I need you to turn over for me. Can you do that? Lie on your stomach sweetie,” He guided, trying to keep his hand pressed against the boy as he shifted, his little belly flat on the mattress. “Perfect.”  
Stiles wriggled a little and flailed, so deep in OmegaSpace that he could barely get his own limbs to function. Derek smiled and watched as his adorable little mate struggled to get his arms to move. “Cross your arms and lay your head on them,” Derek ordered, feeling Stiles melt with relief. He didn’t have to think about anything, which was refreshing as he was normally overthinking everything  
Derek kept his left hand on Stiles’ ass and started to slowly run over the rim with his finger. The finger’s path was smooth and made easy with the addition of warm slick. He cooed constantly at his Omega, rubbing his other hand over the boy’s back, his neck, his ribs, even the slim tangles that were his arms and legs.  
“There, is that better baby?” He asked, knowing Stiles wouldn’t answer, not in this quiet and happy stupor. He kept his hand moving until Stiles broke the silence with a needy whimper.  
“Please, Alpha?” Stiles asked and Derek nearly busted right then, hearing his Omega call him Alpha while in heat and at his mercy.  
Derek melted and tried to soothe his mate. “Of course baby, hold on. Spread your legs for me, as far as they can go.” Derek felt good commanding his mate, helping his mate. He didn’t know if he’d be prepared enough for this when the time came but now he knew that he could provide for his mate just fine.  
There was nothing Derek wouldn’t do for Stiles, and they both knew that. Derek felt assured that Stiles would give himself over to him so willingly, especially this deep in OmegaSpace.  
Stiles spread his legs, his limbs only able to function properly when Derek told them to. His long legs were thin, though well muscled from his runs with Derek in both his forms. He did yoga sometimes, something Laura had taught him to help with his anxiety and sleep, though Derek was suddenly very thankful because it made him more flexible than before.  
Stiles was arching up a little, his hips off the bed. Derek took that opportunity. He took the pillow he usually slept on and brought it closer. “Okay babe, I need you to lift your hips a little higher.” Stiles immediately complied, hitching his hips up and shaking as he tried to maintain the position.  
Derek slid his pillow under the boy’s hip but Stiles’ hips still weren’t high enough. He slid the second pillow under him too and smiled as Stiles relaxed into the cushioned support that was the pillows. “Good job hun,” He praised, the Omega keening under him.  
Stiles whined again and Derek smiled sympathetically and returned his hands to his mate’s body.  
“Baby, I need your permission,” Derek said, “I need your permission to touch you and to help you, can you do that?” He asked sweetly until the boy only nodded. “Speak, Omega,” He demanded and smiled when Stiles yelped and explicitly gave Derek permission. “Good boy, okay, let’s get started.”  
As inexperienced as he was, he knew what Stiles needed. He learned about it in health and was knowledgeable enough to guess what Stiles would like and wouldn’t. He knew Stiles’ body well enough, knew that his boy liked when his bit gently, liked when he was heavy-handed.  
Derek let Stiles shift until he was comfortable, his little cock pressed into the pillow and against his stomach as Derek’s hands pressed Stiles further into the pillows, forcing the boy to be trapped against his own body.  
When he finally stilled Derek took matters into his own hands. He slid his hands to the boys’ hips and rubbed the thicker flesh in his hands. Stiles groaned and whined, pleading and needy. Derek’s hand slipped to Stiles’ ass and gently pulled the cheeks apart, looking for the little treasure. There was little to no hair on Stiles’, an adaption to attract mates, and from here Derek could see the boy’s little balls, nestled against the pillow and offered up to him.  
Derek sucked in a breath and reached under his bed with one hand, reaching for the box of condoms Laura had given him for his birthday and had thought was hilarious. He silently thanked her for her forethought. As much as he wished and wanted to be, neither of them were ready to be dads and Stiles’ body might actually shut down if he tried to carry a pup to full term. Stiles himself was still practically a pup and that would be unfair.  
Stiles looked back and Derek saw a sad look of the Omega’s face. “What’s wrong sweetheart?” He asked, dropping the foil package and dropping both hands to Stiles, who turned over onto his side, his little cock and balls pulled up and tight. There were tears in his boy’s eyes and Derek needed it to stop. “Honey, talk to me,” He demanded.  
“You-you don’t want pups with me?” Stiles whispered, nearly sobbing.  
Derek furrowed his eyebrows for a minute, a little confused before he finally understood. “Oh baby, of course I do, but we both know neither of us are ready. We will when you’re older, okay?” He asked, nearly begging, wanting his mate to stop crying. The boy was letting out sad little sniffles but he nodded anyway. “Okay sweet boy, now. Turn over,” Derek commanded. At least he knew Stiles was deep enough if OmegaSpace. If he hadn’t been they wouldn’t have had this problem.  
Stiles returned to his earlier position and spread wide. Derek didn’t want any more delays and dropped both hands to the boy’s ass, using one the hold them apart and the other to play with the boy’s entrance.  
He rubbed at the wrinkled, pink and slick flesh before dipping his index in, slowly, and keeping still for a moment. He collected himself and began moving it, running it in circles inside his boy. Stiles whined, making happy little noise, though these were different from the happy noises he made when cuddled, these were lower, more primitive.  
Derek bent down and breathed over the little hole, pulling back and watching as it winked at him. When it released Derek dipped in a second finger, scissoring and spreading them slowly and bumping against his mate’s inner walls. “Good boy, just relax,” Derek murmured.  
When he got all four fingers of his hands in his mate he pulled them out, listening, smugly, to the quiet little whimper. Stiles wasn’t whining for very long, because Derek leaned back down, now using both hands to wrench the Omega’s ass apart. He leaned down and sealed his mouth around the boy, sucking and licking. He could taste and swallow Stiles’ slick and vacuumed it into his mouth until he had his fill. “Alright baby, I think we can start. What about you?” He asked before barking at Stiles for an answer, “Answer me, Stiles.” It was the first time, in the entire experience, that he’d called Stiles by his name and that got an instant reaction from the whimpering boy beneath him.  
“Yes, yeah I’m ready,” Stiles whispered, reverent and pliant under his Alpha. Derek nodded, even though Stiles couldn’t see it. He took in a deep breath and leaned back on his feet so he could open the condom and roll it on.  
Breathing deeply, Derek rested the head of his cock against Stiles’ entrance and gently pushed in until the head popped inside. He grunted with the restraint it took to hold himself back. “Alpha, plea-” Stiles didn’t even get to finish as Derek’s Alpha wolf took that as permission and ram-rodded himself, straight into the warm confines that was Stiles’ body.  
Stiles made a happy sound, instead of one of pain, which he was expecting, and shuffled back more, trying to get more inside even though there was nothing left outside of the boy. Derek started slow, rocking inches out before rocking them back in. He continued that way for only a moment before deciding that Stiles could take more and then he started to thrust before giving up all holds on sanity and pistoning himself in and out.  
Stiles squeaked every time Derek’s balls slapped against his ass and groaned whenever he felt Derek touching the very back of him.  
His Omega didn’t scream for him until his dick discovered the boy’s prostate. He slammed against it, which led to Stiles clenching every time that it was even brushed. As Stiles clenched tightly around him Derek felt the base of his dick tingling.  
He knew what that meant. His parents had told him about it because health class didn’t cover the traits specific only to a werewolf’s cock. His dad did though.  
Apparently, he couldn’t speak from experience, as he was a beta, but his brother was an Alpha before he died and told James about it so James could tell his Alpha son.  
“Mate,” Derek huffed, assured as he felt his knot grow. This was a completely new and foreign feeling, happening only when mating and to your true mate.  
He felt the walls around him clenching even harder as his forming knot popped in and out as he continued his thrusting. They remained steady, trying to be calm and consistent for his mate, but finally, he felt that starburst in his stomach and he buried himself in Stiles, knot popping fully and painfully as the skin stretched and nearly tore as he tied himself to his mate.  
Stiles screamed, both in pain and in satisfaction as he buried his face in his arms. “Alpha!” He cried. Even with all the slick, it was still painful. Now, with an Alpha’s knot buried inside him, Derek’s Omega wasn’t leaking anymore; there was a mess of slick coating his ass and the bed sheets beneath them.  
They were both sticky with sweat, and slick.  
Stiles wiggled ad Derek noticed. “Sti? You uncomfortable?” He asked his baby. The boy nodded and Derek cooed at him. “Alright, let’s fix you up,” Derek said, slowly coming out of AlphaSpace and feeling more like himself. Stiles, however, was still nose deep in OmegaSpace and was loose against Derek. With them still tied it was a feat getting more comfortable, Derek bringing Stiles off the bed and into his chest, leaning back together, trying not to let his knot pull on Stiles’ rim too much.  
Finally, he was able to get them settled, propped against the headboard and Stiles resting against his chest and Derek still knotted inside the boy. He knew he was still released and only wished it was inside Stiles and not a fucking condom.  
Derek gently ran his hands over Stiles’ chest and stomach, laughing as Stiles keened happily and scooted back so he was pressed harder against Derek. 

They fell asleep, Derek still buried in Stiles, but when he woke his was limp inside the warm walls and the condom was starting to hurt his oversensitive dick. Stiles’ own cock was red and Derek figured he’d come at least three times while they were fucking. The good news was, as it was Stiles’ first heat, he only needed this once. He knew that as they got older Stiles would need more every heat, but he was exhausted and he knew so was his Omega mate. He lifted Stiles off him and rumbled as he pulled out, his dick flopping out unattractively. 

When they were both awake they showered, together, and dressed. It was morning and they were both starving. The heat had taken a lot out of both of them.


End file.
